Intraocular lenses are widely used to be replaced with human opacity crystalline lenses in cataract treatments or normal human crystalline lenses for compensating the optical powers of the lenses. In intraocular lens insertion surgeries for the cataract treatments, a discission wound (cut) which is several millimeters in length is produced at the edge of the cornea, the human crystalline lens is crushed and removed by phacoemulsification and aspiration etc. and the intraocular lens is inserted and fixed in the eye, for example.
Recently, in inserting an intraocular lens into the inside of an eyeball through the incision, it is often the case that a so-called preload (or preset) type insertion apparatus is used where the intraocular lens is placed in an accommodating member in advance. A user inserts a distal end opening of an inserting sleeve member formed on a distal end member of an apparatus body into the inside of an eyeball through the above-mentioned incision, and also in a state where the intraocular lens is deformed into a compact shape in the inside of the apparatus body, the intraocular lens is pushed out by a rod-like plunger through the distal end opening of the inserting sleeve member so that the intraocular lens is released and inserted into the inside of the eyeball. With the use of such an insertion apparatus, an intraocular lens can be easily inserted into an eyeball by making use of an incision which is formed for taking out and removing a crystalline lens. Accordingly, an operation can be simplified and, at the same time, the occurrence of astigmatism and the occurrence of an infectious disease after the operation can be suppressed.
In inserting an intraocular lens into an eyeball using the above-mentioned insertion apparatus, with an aim to enable smooth movement of the intraocular lens in the inside of the insertion apparatus toward the distal end opening of the inserting sleeve member, there may be a case where viscoelastic material such as hyaluronic acid is injected into the inside of the insertion apparatus as a lubricant for the intraocular lens, and the viscoelastic material is interposed between the intraocular lens and an inner wall of the insertion apparatus. With such a configuration, friction resistance between the intraocular lens and the insertion apparatus is reduced thus enabling the smoother movement of the intraocular lens in the inside of the insertion apparatus. Further, in injecting the viscoelastic material into the inside of the insertion apparatus, a needle of a syringe is inserted into the inside of the insertion apparatus through a hole formed in the insertion apparatus, and the viscoelastic material is injected into particularly a place where the intraocular lens is accommodated in the inside of the insertion apparatus by the syringe.